Adidas Ultra Boost

The adidas Ultra Boost is the latest in the Boost range to get an outing with RunningMonkey and having previously been somewhat ambivalent about both the Adizero Adios Boost and Energy Boost 2.0 we’re finally starting to come round to the adidas way of thinking. Almost…

First the basics: The Ultra Boost is a road shoe that promises great distance with in-built ‘energy-returning properties’ thanks to the boost foam in the midsole. Replacing traditional EVA, boost is composed of fused thermoplastic beads designed to last longer, be less sensitive to temperature changes (i.e. continue to perform even in exceptionally cold weather) and deliver a return of energy as it springs back after each footfall.

In truth the actual boost component still doesn’t have us utterly convinced; yes there’s a spring to the step, but nothing noticeably greater in our experience than a box-fresh set of shoes with EVA. Longevity doesn’t appear to be greatly increased over EVA either, although that’s probably subjective and adidas no doubt have ample lab results to show us otherwise. What is noticeable to RunningMonkey is that they do respond better (or at least don’t respond worse) as the temperature falls. So if you’re looking to rock the ride right through the winter the Ultra Boost could well be worth a look.

That said, the grip – a really unusual arrangement of rubberised dimples – just doesn’t feel up to anything other than bone-dry tarmac. There’s some ‘stickiness’ to the sole, but there’s simply not enough aggression here to tackle anything approaching icy conditions, which seems a shame as cold-weather responsiveness in the foam is such a unique selling point.

The foam-tech aside there’s still a great deal we really do like about the adidas Ultra Boost and, to be reductive, it’s the sheer comfort. They may not be the lightest road shoes at 604g (pair, UK 8.5), but the unusual ‘bootee’ construction into which the foot slides slipper-like is a pleasure to run in. The flex and responsiveness is admirable and the seamless ‘Primeknit’ upper, despite looking like something your gran may have knitted, feels fantastically adaptive against the foot.

Aesthetically the Ultra Boost is an oddly mixed bag – the exoskeleton cradle that maintains integrity beyond the Primeknit looks just plain odd (but does it’s job well) and the Achilles is protected by what looks like a car spoiler. There’s certainly nothing conventionally pretty about these but when it comes to what matters – exceptional comfort over long distances – the Ultra Boost appear to stack up.

The adidas Ultra Boost retails at £130 – full details and online purchase at adidas.co.uk